Cable tie having detachable tail

ABSTRACT

A one-piece cable tie includes a tail which is configured with a plurality of slits or notches therein. These slits are in alignment with the recesses in the tail and extend no deeper than the depth of the recesses. Such slits are designed to aid the use in removing the excess tail from the cable tie once the tie has been tensioned around a bundle. The user first bends the tail so as to close the slits in one side of the tie and then twists the tie about its longitudinal axis so as to separate the excess tail from the tie.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Patent ApplicationNo. 60/706,404, filed on Aug. 8, 2005, which is incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates generally to cable ties for bundling oneor more cables or the like. More particularly, the present inventionrelates to integrally formed one-piece cable ties which permit theremoval of the tail of the tie once bundled.

BACKGROUND OF THE INVENTION

Cable ties have long been used to bundle one or more articles such ascables and the like. These ties are typically plastic elongate strapshaving a tail at one end and a locking head at the other end forreceiving the tail. The head includes a locking mechanism in the form ofan integrally formed locking pawl (one-piece) or an inserted metallicbarb (two-piece).

Both the one-piece and two-piece cable ties operate substantially thesame way in that the free end of the tail is looped around the bundleand pushed or pulled through the head so as to engage the pawl or barbtherein. The cable tie is then tensioned around the bundle as desired.The pawl or barb engages the tail as it passes through the head andprevents the tail from backing out even under a load. The excess tailthen extends outside the head.

While many patents have been issued directed to the shape orconstruction of the cable tie, its barb or pawl, and/or its head, fewaddress the removal of the excess tail from the cable tie once the tiehas been installed. Instead, the user is left to his/her own devicessuch as employing a tool to cut the excess length off.

U.S. Pat. No. 3,739,430 is an early attempt at providing some mechanismof removing the excess tail length from the tie after tensioning. Inaccordance with this patent a series of slits are cut into the oppositeshorter sides of the strap at spaced intervals. After the tail is pushedthrough the head, the tail is twisted about its longitudinal axis asshown in FIGS. 4 and 9 until the tail separates from the tie. While thismethod enables a user to detach a two-piece cable tie tail without usingtools, this method is not suitable for one-piece cable ties. This isbecause these side slits will significantly reduce the cross-sectionalarea of the one-piece tie and hence such a side-slitted cable tie cannotattain the same rating as its un-slitted twin.

While this side-slitting method is suitable for two-piece cable ties,such technology is not readily transferable to one piece cable ties.This is because two-piece cable ties generally have a smooth planar tailwith no interruptions, ridges or teeth therein since it is intended forthe metal barb to bite into the tail at any location along its length.In other words, its cross-sectional area is constant along the length ofthe tail. In contrast, the tail of one-piece cable ties are speciallydesigned with at least one surface (and maybe its opposite surface too)configured with a series of ridges or teeth therein that are intended tobe engaged (not embedded) by the pawl. Hence, the cross-sectional areaof the tail of a one-piece cable tie varies depending on whether theview is through a tooth or the space between adjacent teeth. Thus, theplacement of side slits as shown in the '430 patent will compromise thestrength of a one-piece cable tie if the slits align with the recessbetween the teeth. This is because the slit would further erode theload-bearing cross-sectional area of the tie thereby rendering it onlymarginally useful.

SUMMARY OF THE INVENTION

It is thus an object of this invention to provide a one-piece cable tiewhere the excess tail length can be removed by a user without the needfor tools or knives.

It is a further object of this invention to provide a one-piece cabletie whose excess tail length can be removed by the simple act oftwisting or bending.

A further object of this invention is to provide a one-piece cable tiedesigned so that its excess tail length can be removed without adverselyaffecting the strength of the cable tie when under tension.

A one-piece cable tie includes a head, a strap extending from the headand a tail forming at least a portion of the strap, this tail beingconfigured with a plurality of spaced teeth and spaced recesses in atleast a first surface thereof. The cable tie is also configured with afirst plurality of spaced slits in the first surface which are inalignment with the spaced recesses. The cable tie is also configuredwith a second plurality of spaced slits in a second surface of the tailopposite this first surface.

In one version of the cable tie, the first plurality of spaced slitsextend no deeper than the depth of the recesses. In another version ofthe cable tie, the first and second plurality of spaced slits are inalignment with each other. In yet another version of the cable tie,there are opposite side surfaces intermediate the first and secondsurfaces and the tie is configured wherein a mid-portion of the tailextends fully from one side surface to the other without any slitstherein along the length of the tail.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear perspective view of the cable tie of the presentinvention.

FIG. 2 is a front perspective view of the cable tie of the type shown inFIG. 1.

FIG. 3 is a side elevational view of the cable tie of FIG. 2.

FIG. 4 is a rear perspective view of a portion of the cable tie strap ofFIG. 1.

FIG. 5 is a cross-sectional view of the cable tie of FIG. 3 taken alonglines 5-5 thereof.

FIG. 6 is a cross-sectional view of the cable tie of FIG. 3 taken alonglines 6-6 thereof.

FIG. 7 is a perspective view of the cable tie of the present inventionbundled about a cable with the tail shown removed.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings, there is shown one-piece cable tie 10 havinga tail 12 forming all or a part of an elongated strap, a head 14 and aflexible pawl 16 all generally made of a suitable plastic material andgenerally manufactured by an integral molding process.

The parallel teeth 18 that run along a bottom surface 20 of tail 12while FIG. 2 illustrates the generally smooth planar top surface 22 ofcable tie 10. While such is the preferred embodiment, both sides of tail12 could be configured with teeth 18 therein if desired.

Teeth 18 and pawl 16 of this embodiment are specially designed forone-way ratchet-type inter-engagement in order to keep cable tie 10securely bundled or tensioned about cables and the like as is well knownin the art.

The strap includes recesses 24 intermediate teeth 18. The recesses 24are evenly spaced and permit a portion of pawl 16 to fit therein andengage one or more surfaces of teeth 18 so as to prevent tail 12 frombeing pulled back out of head 14.

Running the length of tail 12 alongside both teeth 18 and recesses 24are exterior rails 26. Rails 26 help align pawl 16 with teeth 18 andthey also aid in the insertion of tail 12 within head 14 as they providestiffness to tail 12. The tail of the one-piece cable tie 10 is acontinuous piece of uniformly shaped material, but with the tail 12having uniform recesses 24 formed therein to approximate a “scooped out”configuration of at least bottom surface 20 intermediate rails 26.

The present invention provides for severing the excess tail length froma tensioned tie is without using cutters or knives or the like.

In the present embodiment, a series of spaced notches or slits 28 areformed into bottom surface 20 of tie 10. A like series of slits 30 arefound in the top surface 22 of tie 10. Bottom surface slits 28 extendonly to the depth of recess 24 as shown in FIG. 4. This is the maximumdepth of slits 28. The slits 28 may be shallower in the recess 24. Topsurface slits 30 are not so confined. The slits 28 and 30 have a depthsuch that the strength of the cable tie is not adversely affected whichcould render it inadequate or too weak to attain its un-slitted ratedstrength. Also, as can be seen from the drawings, slits 28 and 30 areprimarily confined to rails 26 so as not to interfere with teeth 18 ofcable tie 10. Further, it should be noted that these slits 28 and 30 arefound in the top 22 and bottom 20 surfaces of tail 12 and not its sides.This allows the sides of the tail 12 to remain substantially intact.

FIG. 5 shows a cross-section through a tooth 18 of the cable tie 10.This is the maximum amount of cross-sectional surface area for tie 10.In contrast, FIG. 6 shows a cross-section through a recess of cable tie10. This is the minimum amount of cross-sectional surface area for tie10. FIG. 6 illustrates recess 24, bottom slit 28 and top slit 30. Rails26 can also be distinguished. The slits 28 and 30 do not meet or are notjoined. Moreover, no cutting or notching of rail 26 occurs at theminimum cross-section surface area shown in FIG. 6 as the surface areamust still be sufficient enough to withstand the load placed upon cabletie 10. Thus, the slits are provided along the cable tie, withoutreduction to its rated strength. Hence, while bottom 20 and top 22surfaces contain slits therein, the adjoining side surfaces 32 remainfree of slits. A mid-region 34 of tail 12 extending from one sidesurface 32 to the other remains un-slitted and hence continuous alongits length, this mid-region 34 being illustrated in FIG. 6. Top surfaceslits 30 have been found desirable so as to help encourage the stressbreakage of tail 12.

Referring now to FIG. 7, in operation, once the cable tie 10 is bundledabout cables 30, with the tail extending through head 14, the excesstail 12 length is first bent so as to close-up bottom surface slits 28and open-up top surface slits 30. The tail 12 is then rotated about itslongitudinal axis (say clockwise as indicated by arrow A) until it isseparated from the body of the head 14. This creates a frangiblelocation on the cable tie strap which allows the strap to be severed atthe head upon said manual twisting. The slits 28 and 30 are positionedat a fixed distance from teeth 18 such that when the tail is severedfrom the head there is no excess material protruding from the head.

The benefit of top surface slits 30 becomes evident in this bendingabout the longitudinal axis. It has been found that without slits 30,such longitudinal twisting does not create the desired stresses in topsurface 22 whereas with slits 30, the excess tail length is readilyremoved from tie 10. Bottom slits 28 help overcome the rigidity andstrength that rails 26 provide to tail 12 during this removal operation.Further, by incorporating top and bottom slits 28 and 30, rather thanside slits, the cable tie 10 is more flexible and hence easier to fitaround a bundle. It should also be noted that with slits beingconfigured in both top and bottom surfaces 20 and 22, the tail 12 can bebent and/or twisted in a direction opposite to that described above andstill be equally removable.

Various changes to the foregoing described and shown structures wouldnow be evident to those skilled in the art. Accordingly, theparticularly disclosed scope of the invention is set forth in thefollowing claims.

1-14. (canceled)
 15. A one-piece cable tie comprising: an elongated tailextending from a head, said tail configured with a plurality of spacedteeth and spaced recesses in at least a first surface thereof, said headhaving an integrally formed locking pawl for engagement with said tailteeth; and a first plurality of spaced slits in said first surface, saidslits being in alignment with said spaced recesses and defining afrangible location for severing a portion of said tail thereat uponinsertable accommodation of said tail in said head.
 16. The one-piececable tie as set forth in claim 15 wherein said spaced slits extend nodeeper than the depth of said recesses.
 17. The one-piece cable tie asset forth in claim 15 further comprising a second plurality of spacedslits in a second surface of said tail opposite said first surface. 18.The one-piece cable tie as set forth in claim 17 wherein said first andsecond plurality of spaced slits are in alignment with each other. 19.The one-piece cable tie as set forth in claim 15 further comprisingopposite side surfaces intermediate said first and second surfaces andwherein a mid-portion of said tail extending fully from one side surfaceto the other is unslitted along the length of said tail.
 20. A one-piececable tie of claim 15 wherein said slits are spaced from said teeth agiven distance such that severing said tail at said slits results in thesevered end of the tail being substantially flush with the head.